Coupling for webs

ABSTRACT

A coupling is disclosed for securing adjacent end web portions without overlap of the webs. The coupling includes series of spaced loops which project endwise from the end portions of the webs and are held in intermeshing relationship by a connector which is threaded through the intermeshing loops and comprises a pair of parallel rods which are freely movable related to one another and convexly curved in cross-sectional profile at least where the rods make contact with each other and which are enclosed in a resilient tube.

United States Patent Bartmann June 13, 1972 COUPLING FOR WEBS FOREIGNPATENTS OR APPLICATIONS [72] Inventor: Otto Bartmann, 6 Waldstn, Birgel,Duren, 1,494,161 7/1967 France ..24/33 C German 23 y OTHER PUBLICATIONS22 F1 d: ul 1970 Y 1 J y 1808995 German Printed Application 2/1970 SCAPADryers [21] Appl. No.: 57,446 pgs. 3 & l4.

Primary Examiner-Donald A. Griffin [30] Application mm'ityAttorney-Dawson, Tilton, Fallon & Lungmus Jul 24, 1969 Gennan ..G 69 29255.3

y y 57 ABSTRACT [5 2] US. Cl. ..24/33 C A coupling is disclosed forsecuring adjacent end web portions [51] Int. Cl. ..F16g 3/02 withoutoverlap of the webs. The coupling includes series of [58] Field ofSearch ..24/90 TS, 31 H, 33 M, 33 C, spaced loops which project endwisefrom the end portions of 24/33 P, 33 A, 33 R; 74/231 J the webs and areheld in intermeshing relationship by a connector which is threadedthrough the intermeshing loops and 56] References Cited comprises a pairof parallel rods which are freely movable related to one another andconvexly curved in cross-sectional UNITED STATES PATENTS profile atleast where the rods make contact with each-other and which are enclosedin a resilient tube. 2,629,909 3/1953 Hall ..24/33 C Diamond ..24/33 C 9Clairm, 5 Drawing COUPLING son wsas This invention relates to belt andweb couplings enabling different belts or webs or different end portionsof a given belt or web to be releasably coupled end to end withoutoverlap.

The invention has been made primarily for embodiment in endless wiresand felts for paper or board-making machines.

A known and useful type of coupling is one in which each of the belt orweb ends to be coupled together is provided with a series of spaced wireloops and the different series of loops are held in intermeshingrelationship by a rod which is threaded through the intermeshing loops.The different series of coupled loops can articulate about theconnecting rod and an endless belt or web formed by coupling the ends ofone or more webs or belts by means of such a coupling or couplings cantherefore travel over supporting and driving rollers of small radius.There is need for improvement in this type of coupling however. Whenused in a heavy duty endless machine belt or web, e.g., a felt or wireof a paper-making machine, the connecting rod is subject to suchconsiderable surface wear and tractional force that it is liable sooneror later to become deformed so that the machine felt or wire does notrun truly at the seam, and the connecting wire or rod iseven liable tobreak, with risk of serious damage to the machine and of injury topersonnel. The liability to failure of the connecting rod is undoubtedlyincreased if the seam becomes contaminated with corrosive substances orif dirt or foreign matter accumulates in the seam.

According to the present invention, end portions of a belt or web or endportions of different belts or webs' are coupled without overlap by acoupling comprising series of spaced loops which project endwise fromthe said end portions and are held in intermeshing relationship by aconnector which is threaded through the intermeshing loops and comprisesa pair of parallel rods which are convexly curved in cross-sectionalprofile at least where the rods make contact with each other and whichare enclosed in a resilient tube.

A coupling as above defined has been found to have a longer useful lifethan the known couplings of similar type as hereinbefore referred to.The connector is very resistant to deformation. In general, anydeformation is restricted to denting'of the resilient outer tube. Ifthis denting occurs it does not cause difficulty in removing theconnector because the rods can be withdrawn first, if required one at atime,'leaving the tube for withdrawal afterwards.

The outer tube protects the vital contacting bearing surface of the rodsfrom dust and other deposits, also from steam. By virtue of theprotection afforded by the outer tube, the rods can be made from lessexpensive material than would otherwise be required. By way of example,the rods may be made from a material of high mechanical strength whichis not corrosion-resistant, such as steel cord.

Notwithstanding that the connector comprises two relatively movablebearing rods, it is insertable into and withdrawable from connectingposition, as a unit, and coupling and uncoupling can therefore be veryeasily accomplished.

Another important advantage of the invention is that if lubricant isapplied to the relatively sliding surfaces of the rods the outer tubehelps to retain the lubricant as well as to keep the lubricant free fromfouling by dirt. It is very advantageous for lubricant to be presentwithin the outer tube, and particularly between the rods. According to aparticular embodiment, the rods carry a lubricant film of syntheticplastics material, at least at those zones which are in sliding contact.The rods may actually be attached or caused to adhere to each other bymeans of a lubricant or a rubber-like synthetic plastics or naturalmaterial. Polytetrafluoroethylene has proved a suitable material forthis purpose. Such attachment facilitates insertion of the rods into theouter tube and makes it easier to ensure that the rods are parallel witheach other in the plane of the seam when the connector is threadedthrough the loops.

The rods may be of any cross-sectional dimensions suited to thecircumstances of use. The term rod" is not to be taken as implying anyparticular minimum thickness but is used broadly to include an elementwhich could properly be called a wire. The rods may be of compositestructure, e.g., they may be formed of braided strands. Preferably therods are each formed in one piece, which may however be coated.

The outer tube requires to be resilient so that tractional forces acrossthe seam are transmitted to the rods. Preferably the outer tube is madeof a resilient synthetic plastics material. Examples of suitablematerials for the outer tube are polytetrafluoroethylene, polyester andpolyamide. The presence of the outer resilient tube substantiallyreduces wear of the interconnected series of loops.

The outer tube is preferably sealed, e.g., by welding, at one or bothends. In this sealing operation, at least one end of the outer tube maybe drawn out or otherwise formed to a taper to facilitate threading ofthe connector through the loops. Alternatively or in addition, aseparate cap piece may be fitted to the assembly of rods, which cappiece may itself be pointed.

The invention particularly includes a felt or wire of a paper orboard-making machine, such felt or wire comprising a single length ofmaterial of appropriate composition and structure (such length ofmaterial constituting a web" within the meaning of that term as usedherein), the end portions of such length of material being jointed by acoupling as herein defined. The seam of such a felt or wire is veryresilient and in consequence there is less tendency than when usingknown couplings for undulations to appear in the felt or wire. of courseit is possible to form a felt or wire from two or more lengths ofmaterial by incorporating two or more seam couplings.

Certain embodiments of the invention, selected by way of example, willnow be described with reference to the accompanying drawings in which:

FIG. 1 is a plan view of part of a paper machine felt or wire accordingto the invention;

FIG. 2 is a cross-sectional view showing two coupling loops andathreaded connector as used in the seam of the felt or wire shown in FIG.1;

FIG. 3 is a cross-sectional view of coupling components of anotherembodiment of the invention;

FIG. 4 shows part of a connector; and

FIG. 5 is a cross-section on line V-V of FIG. 4.

Referring fustly to FIGS. 1 and 2: the felt is provided with two seriesof spaced loops 1,1 which are connected to the end portions 2,2 of theweb of material constituting the felt or wire. The loops project endwisefrom the opposed end portions of the felt or wire and the loops are heldin intermeshing relationship by a connector 3 which is threaded throughsuch loops, thereby making a hinge-like joint.

The connector '3 comprises two rods, 4,4 disposed side by side inparallel in the plane of the seam, and an outer tube 5. the rods 4,4 arefreely movable relative to each other within the tube 5, even though therods may be caused to adhere to each other by means of a lubricant tofacilitate insertion of the rods into the outer tube. The rods 4,4 may,e.g., be composed of stainless steel with a polyamide coating or ofpolyamide monofilaments with a synthetic-resin-impregnated polyestercoating. The outer tube 5 may be formed, e.g., ofpolytetrafluoroethylene. A lubricant may be provided inside the outertube 5, preferably between the rods 4,4'.'This lubricant may containmolybdenum disulphide and/or graphite or it may be a synthetic plasticmaterial with lubricating properties, e.g., polytetrafluoroethylene.Alternatively the lubricant may be a conventional lubricant paintapplied as a coating film to the rods 4,4. Alternatively a rubber-likeadhesive may be provided instead of alubricant.

It will be noted that the rods 4,4 are not of circular section but theircross-sections are convexly curved at the sides where the rods are inbearing and sliding contact. Other cross-sectional shapes, e.g., an ovalshape, are acceptable provided that the rods are rounded to permitsliding or rolling motion when the series of loops 1,1 hinge about thejoint axis.

FIG. 3 shows a construction in which the rods are of circularcross-section. In the FIG. 3 embodiment a lubricant or rubberlikeadhesive is present within the outer tube and is marked 6.

Advantageously, the outer tube 5 is sealed or closed at least at oneend. In the form of connector represented in FlG. 4 a pointed end cap 7is titted to form the end of the connector which is first to beintroduced through the seam loops. As appears from the cross-sectionalview (FIG. 5) the cap is fonned with semi-cylindrical grooves 8,8 whichreceive end portions of the rods 4,4. The cap could be formed with boresinstead of the grooves 8,8.

I claim:

1. A'belt or web coupling whereby end portions of a belt or web or endportions of different belts or webs are coupled without overlap, saidcoupling comprising series of spaced loops which project endwise fromthe said belt or web end portions and are held in intermeshingrelationship by a connector which is threaded through the intermeshingloops, such connector comprising a pair of parallel rods which areconvexly curved in cross-sectional profile at least where the rods makecontact with each other and which are enclosed in a resilient tube andfreely movable relative to each other within said tube.

2. A belt or web coupling according to claim 1 wherein the saidresilient tube is made of synthetic plastics material.

3. A belt or web coupling according to claim 2, wherein the rods bearfilms of synthetic plastics lubricant at least at those zones where therods are in' contact with each other.

4. A belt or web coupling according to claim 3, wherein the said rodsare attached or caused to adhere to each'other by means of a syntheticplastics lubricant or rubber-like material.

5. A belt or web coupling according to claim 3, wherein the rodsare-attached to each other by polytetratluoroethylene.

6. A belt or web coupling according to claim 3, wherein the resilienttube is fonned of a therrnoplastics material and one end of the tube hasbeen heat sealed and drawn out to form a pointed connector end. 1

7. A belt or web coupling according to claim 5, wherein at least one endof the resilient tube is closed by an end cap having grooves or boresaccommodating end portions of the said rods.

8. A belt or web coupling according to claim 3, wherein at least one endof the resilient tube is sealed or otherwise closed to enclose thecorresponding ends of the rods.

9. A belt or web coupling according to claim 1, wherein lubricant ispresent within said resilient tube.

l i l l

1. A belt or web coupling whereby end portions of a belt or web or endportions of different belts or webs are coupled without overlap, saidcoupling comprising series of spaced loops which project endwise fromthe said belt or web end portions and are held in intermeshingrelationship by a connector which is threaded through the intermeshingloops, such connector comprising a pair of parallel rods which areconvexly curved in cross-sectional profile at least where the rods makecontact with each other and which are enclosed in a resilient tube andfreely movable relative to each other within said tube.
 2. A belt or webcoupling according to claim 1 wherein the said resilient tube is made ofsynthetic plastics material.
 3. A belt or web coupling according toclaim 2, wherein the rods bear films of synthetic plastics lubricant atleast at those zones where the rods are in contact with each other.
 4. Abelt or web coupling according to claim 3, wherein the said rods areattached or caused to adhere to each other by means of a syntheticplastics lubricant or rubber-like material.
 5. A belt or web couplingaccording to claim 3, wherein the rods are attached to each other bypolytetrafluoroethylene.
 6. A belt or web coupling according to claim 3,wherein the resilient tube is formed of a thermoplastics material andone end of the tube has been heat sealed and drawn out to form a pointedconnector end.
 7. A belt or web coupling according to claim 5, whereinat least one end of the resilient tube is closed by an end cap havinggrooves or bores accommodating end portions of the said rods.
 8. A beltor web coupling according to claim 3, wherein at least one end of theresilient tube is sealed or otherwise closed to enclose thecorresponding ends of the rods.
 9. A belt or web coupling according toclaim 1, wherein lubricant is present within said resilient tube.